diff --git a/src/AndGate.h b/src/AndGate.h
index b373c60..7ea8ed4 100644
--- a/src/AndGate.h
+++ b/src/AndGate.h
@@ -4,6 +4,8 @@
 #include "Event.h"
 #include "Wire.h"
 
+using namespace std;
+
 class AndGate : public Gate {
 	public:
 		AndGate(int d, Wire* wire1, Wire* wire2, Wire* wire3);
diff --git a/src/NorGate.h b/src/NorGate.h
index c39d900..9b6cfc1 100644
--- a/src/NorGate.h
+++ b/src/NorGate.h
@@ -4,6 +4,8 @@
 #include "Event.h"
 #include "Wire.h"
 
+using namespace std;
+
 class NorGate : public Gate {
 	public:
 		NorGate(int d, Wire* wire1, Wire* wire2, Wire* wire3);
diff --git a/src/NotGate.h b/src/NotGate.h
index 1721119..5260397 100644
--- a/src/NotGate.h
+++ b/src/NotGate.h
@@ -4,6 +4,8 @@
 #include "Wire.h"
 #include "Event.h"
 
+using namespace std;
+
 class NotGate : public Gate {
 	public:
 		NotGate(int d, Wire* wire1, Wire* wire2);
diff --git a/src/OrGate.h b/src/OrGate.h
index 514e8d3..f8b9a5a 100644
--- a/src/OrGate.h
+++ b/src/OrGate.h
@@ -4,6 +4,8 @@
 #include "Event.h"
 #include "Wire.h"
 
+using namespace std;
+
 class OrGate : public Gate {
 	public:
 		OrGate(int d, Wire* wire1, Wire* wire2, Wire* wire3);
diff --git a/src/XnorGate.h b/src/XnorGate.h
index af2c438..e775521 100644
--- a/src/XnorGate.h
+++ b/src/XnorGate.h
@@ -4,6 +4,8 @@
 #include "Event.h"
 #include "Wire.h"
 
+using namespace std;
+
 class XnorGate : public Gate {
 	public:
 		XnorGate(int d, Wire* wire1, Wire* wire2, Wire* wire3);
diff --git a/src/XorGate.h b/src/XorGate.h
index 53da962..b147af8 100644
--- a/src/XorGate.h
+++ b/src/XorGate.h
@@ -4,6 +4,8 @@
 #include "Event.h"
 #include "Wire.h"
 
+using namespace std;
+
 class XorGate : public Gate {
 	public:
 		XorGate(int d, Wire* wire1, Wire* wire2, Wire* wire3);